What it is
A back-of-the-neck operation in which the surgeon removes bone and ligament to decompress the spinal cord over multiple levels, and then fuses the segments with screws and rods.
When it's used
PCDF is generally chosen for multilevel problems — for example, spinal cord compression (myelopathy) across several levels, especially when there is instability or a reversed (kyphotic) curve, or when disease spans too many levels to address well from the front. It provides broad decompression and strong stabilization at the cost of a larger posterior exposure and loss of motion at the fused levels.